This week, when Colorado lawmakers return for the 2016 legislative session, much of the attention will focus on the partisan gridlock between the Republican-led Senate and the Democratic-controlled House.

A less-noticed dynamic, poised to detonate in the election-year term, is a conservative split among Republicans in the Senate. The divide threatens the party’s efforts to present a unified front.

The vast majority of the Senate votes against legislation in the 2015 session came from Republicans, rather than Democrats, according to a Denver Post analysis using data from the nonpartisan bill-tracking service Colorado Capitol Watch.

The Post’s findings point to a reversal of the typical voting pattern, particularly given that the majority party determines which legislation advances to the floor and often kills measures it opposes in committee.

“Republicans have splattered all over the place,” said Paula Noonan, a principal at Colorado Capitol Watch and a former Democratic school board member.

Eight conservative senators — essentially a Colorado version of the congressional “Freedom Caucus” — led the protest that split Republicans on issues related to taxes and spending, regulation and social issues.

The bills that drew opposition from half or more of the 18-member GOP caucus included measures to expand a tax credit for historic buildings, continue the regulation of elevator mechanics, spend more on a school lunch program for needy students and expand government-paid treatment for children with autism.

The lawmakers argued that these measures and dozens of other bills advanced under Senate President Bill Cadman, a Republican from Colorado Springs, were not conservative enough.

“I think a lot of the no votes were … this expansion of government into the lives of people,” said Sen. Tim Neville, a Littleton Republican running for the U.S. Senate, and one of the eight lawmakers. “Also, I think there’s a frustration we are seeing with government actually getting involved in picking winners and losers — that’s a problem.”

The voting pattern reflects the ideological divide in the national Republican Party, most obvious in the 2016 presidential contest, and showcases the tensions that will influence which bills win approval when the legislature convenes Wednesday.

The top issues this session include a state budget shortfall, money for roads, potential spending cuts to education and a lack of affordable housing.

With GOP leaders in both chambers term-limited after this year, the upcoming session will open the door to rank-and-file Republican lawmakers to set the party’s direction for the future.

Senate, House contrast

In the Senate, Republicans united on six out of every 10 bills sent to the governor in 2015, but typically half the legislation each session is noncontroversial, making the GOP fractures even more prominent.

Given the party’s narrow 18-17 majority in the Senate, the dissension forced Cadman to rely on support from Democratic lawmakers to pass about 40 percent of the 367 bills that won approval in both chambers, The Post’s analysis found.

“This doesn’t mean that Cadman is a closet Democrat,” said Noonan, who has reviewed the legislative data, “but that the Democrats have moved right and conservative Republicans have moved righter.”

The party discipline in the House, despite its own factions, provides a stark contrast to the Senate.

Democrats, who hold a 34-31 majority in the chamber, voted in unison on 85 percent of the bills sent to the governor.

Only once did a majority of the Democratic caucus vote against a bill that went to the governor — a measure to limit red-light traffic cameras.

What further highlights the distance between the House and Senate is the vote differential that separates each chamber’s leader and the party member who most often broke ranks.

In the House, Speaker Dickey Lee Hullinghorst voted against four bills. Denver Democrat Dan Pabon, the speaker pro tem, cast the most “no” votes at 11.

“The lack of party discipline on policy for Republicans is not a new thing and something they pride themselves in,” said Mike Beasley, a veteran lobbyist and former legislative liaison for Republican Gov. Bill Owens. “On the Democratic side, discipline helped them turn Colorado purple. Democrats run a very tight shop.”

Senate President pro tem Ellen Roberts, R-Durango, put it more succinctly: “We do our disagreements in public more than Democrats do.”

Recalls “House Crazies”

The current situation is drawing comparisons to the 1970s, when firebrand conservative Tom Tancredo helped lead the ” House Crazies” in the General Assembly. And legislative veterans suggest the increasing polarization of the state’s political climate is to blame.

“I think we were less divided back in my time,” said Norma Anderson, a 19-year lawmaker who led the GOP caucus in the House and Senate before retiring in 2005. She said the current Republicans voting against the party leadership represent the “ultra-right.”

Even compared to 2014, when Democrats held power in the Senate, the present posture represents a shift for Republicans. As the minority party, the GOP voted together more often, about 80 percent of the time on contested bills.

In an interview, Cadman played down any concerns about internal friction in the current GOP majority, saying the vote patterns show that “representative government works.”

The eight Republicans who most often opposed Cadman’s position include three members of the caucus leadership team and three other committee chairmen.

Of the group, four — Marble, Neville, Jerry Sonnenberg of Sterling and Randy Baumgardner of Hot Sulphur Springs — voted against Cadman’s position at least one out of every five times, the analysis showed.

Other Republicans joined the opposition on various bills, and the lawmakers asserted that there is no formal conservative caucus within the GOP ranks.

But the eight Republicans are listed as the top ranking lawmakers on the scorecard from the organization Principles of Liberty, which grades votes based on a range of libertarian-aligned values.

Cadman, who received an F on the report, said Republicans who opposed the bills “maybe should have exerted a little more influence before they got to the floor.”

“Independent thinker”

Most of the eight lawmakers represent strong Republican districts, where ideological extremes often triumph.

The two exceptions are Neville and Sen. Laura Woods, R-Arvada, who faces a tough re-election bid this year. Both suggested their voting records reflected their districts and their values.

“If you’ve looked at my voting record at all, what you will know is I’m an independent thinker,” said Woods, whose district is evenly split between the parties and independents. The values that guide her votes, she said, are liberty, smaller government, personal responsibility and fiscal restraint.

“I bucked my leadership, I bucked the party, I bucked the caucus … if it didn’t line up with my principles or my district,” she said.

Republican leaders in both chambers tout their open-ended system and criticize Democrats for marching in lock step. The critics recall when the House speaker stared down a few Democratic lawmakers to pressure them to change their vote on a procedural motion to delay a vote on a bill to regulate powdered alcohol.

But Hullinghorst, D-Boulder, suggested the cohesion gives the party a clear message and vision to take to voters in an election year.

“We work really hard on our agenda, and we are on the same page on a lot of things,” she said. “We are independent thinkers. But … to do the things we really want to get done, we know we have to be unified.”

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